Planchuelo-Gómez A, et al. - In the present study, researchers performed a detailed comparison of the white matter in episodic migraine (EM), chronic migraine (CM) and healthy controls over a large cohort of individuals, using diffusion MRI (dMRI) data. In the final analysis, they included 50 healthy controls, 54 episodic migraine and 56 chronic migraine patients who underwent brain T1-weighted and diffusion-weighted MRI acquisition. In patients with chronic migraine, they observed significant decreased axial diffusivity compared with those with episodic migraine in 38 white matter regions from the Johns Hopkins University ICBM-DTI-81 White-Matter Atlas. Time from onset of chronic migraine had a significant positive correlation with mean fractional anisotropy in the bilateral external capsule, and had a negative correlation with mean radial diffusivity in the bilateral external capsule. These findings suggest that patients with episodic migraine and chronic migraine exhibit differences in global white matter structure. In the first months of chronic migraine, patients with chronic migraine could display axonal integrity impairment with respect to episodic migraine patients. After the onset of chronic migraine, white matter changes might indicate a set of maladaptive plastic changes.